| 摘要 |
The modulus of elasticity and yield strength of a rigid core rod are set within predetermined limits as to limit the elastic deformation and prevent plastic deformation of a dental tray during multiple impression taking, bite registration and subsequent handling. The tray is formed with a frame which provides a positive recovery force when it is flexed. The cross section of the core rod may be optimized to further limit deflection in a predetermined plane. Various preferred materials including nonwoven spun-bonded filaments are selected for supporting impression material on the tray while minimizing the likelihood of obstructing a patient's teeth during full occlusion. |
